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(11) | EP 1 644 443 B1 |
| (12) | EUROPEAN PATENT SPECIFICATION |
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A METHOD OF PRODUCING AN INTERPENETRATING POLYMER NETWORK (IPN), THE IPN AND USE THEREOF VERFAHREN ZUR HERSTELLUNG EINES INTERPENETRIERENDEN POLYMERNETZWERKS (IPN), DAS IPN UND DESSEN VERWENDUNG PROCEDE PERMETTANT DE PRODUIRE UN RESEAU POLYMERE INTERPENETRANT (IPN), IPN RESULTANT ET UTILISATION DE CELUI-CI |
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| Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention). |
TECHNICAL FIELD
[0001] The present invention relates to a method of producing an interpenetrating polymer network (IPN) and an IPN obtainable according to the method as well as applications of such IPN.
BACKGROUND ART
[0002] IPNs have been known for more than 40 years. IPNs are defined as macromolecular assemblies comprising two or more polymers wherein at least one is in the form of a network, the polymers are at least partially interlaced on a molecular scale but not covalently bonded to each other.
[0003] Because there is no chemical bonding between the networks (or polymer/network), each network may retain its individual properties independently of its individual proportion in the blend. As a result an improvement can be attained in properties such as mechanical strength, impact resistance, and toughness and other. There are two main types of IPNs, viz semi-IPN where at least one component is not in network form, and full IPN where all species are in network form.
[0004] US 2002/01222946 relates to a process of producing an IPN comprising: providing a liquid mixture comprising silicone oligomers and silsesquioxane oligomers; and curing the liquid mixture to form a composition of first and second polymers, the first polymer comprising the silsesquioxane oligomers cross-linked by siloxane bonds and the second polymer comprising a cross-linked silicone network formed in part from the silicone oligomers.
[0005] US 20030000028 provides a colorant for use in tinting contact lenses in which the binding polymer used is capable of forming an interpenetrating polymer network with the lens material. When the colorants of the invention are applied to uncured lens material that is subsequently cured, the binding polymer forms an interpenetrating polymer network with the lens material embedding the colorant within the lens material, resulting in a stable, tinted lens.
[0006] Several other methods for producing IPNs are known. The methods e.g. include simultaneously forming and cross-linking the polymer networks in the presence of each other. Other methods include forming a first network and thereafter swelling this network with monomers, cross-linking agents and optionally initiator/catalyst with or without solvents whereafter this monomer may form a polymer and optionally a network, e.g. as disclosed in US 2002/0052448.
[0007] Prior art silicone IPN's are made by vulcanizing or cross-linking block copolymers, such as adducts of silicone molecules and other polymer blocks, such as ethers, urethanes, and the like. However, in the use of prior art methods, the types of silicone IPNs and the freedom of design of properties of the IPNs are very limited.
[0008] Even though there are a lot of well working methods for producing IPNs there is still a need for new alternative methods in particular for producing silicone IPNs.
SUMMARY OF INVENTION
[0009] The objective of the present invention is to provide an alternative or an improved method of producing an IPN, which method is simple to use and inexpensive, and whereby a full IPN can be obtained.
[0010] Furthermore it is an objective to provide a method of producing an IPN, which method also can be used for the production of IPNs which are complicated or impossible to produce using the prior art methods.
[0011] This and other objectives as disclosed in the following description have been achieved by the invention as it is defined in the claims and described in the description.
[0012] The inventor has thus found that by using a solvent with low surface tension for monomers to be precipitated within a silicone polymer composition, it is possible to load monomers into the silicone polymer composition very fast and furthermore it is possible to load monomers which previously have not been possible to load into silicone polymer compositions.
[0013] Furthermore the amount of monomers that can be loaded into the silicone polymer composition may be relatively high compared with prior art methods.
DISCLOSURE OF INVENTION
[0014] The method according to the invention of producing an interpenetrating polymer network (IPN) comprises the following steps:
- i) providing a silicone polymer composition,
- ii) providing one or more monomers for a polymer,
- iii) providing a solvent for the one or more monomers,
- iv) exposing said silicone polymer composition to said one or more monomers and said solvent in liquid or supercritical state to precipitate monomer within said silicone polymer composition
- v) polymerizing said monomer to form an IPN.
[0015] The silicone polymer composition may in principle be any type of silicone polymer composition, but basically the best result is obtained if the silicone polymer composition comprises at least 10 %, such as at least 20%, such as at least 40%, such as at least 60 % by weight of polymer having a backbone consisting of Si and O molecules.
[0016] In one embodiment, the silicone polymer composition comprises at least 10 %, such as at least 20%, such as at least 40%, such as at least 60 % by weight of polymer having a backbone consisting of Si molecules.
[0017] In one embodiment, the silicone polymer composition comprises at least 10 %, such as at least 20%, such as at least 40%, such as at least 60 % by weight of polysiloxane polymer.
[0018] Examples of useful silicones which separately or jointly can be comprised in the silicone polymer composition are dimethyl polysiloxan, methylphenyl polysiloxane, fluorosilicone rubber, silicone esters, polysiloxanes, polysilanes, chlorosilanes, alkoxysilanes, aminosilanes, polysilanes polydialkylsiloxanes, polysiloxanes containing phenyl substituents, said polymers of the silicone polymer composition optionally being vinyl-functionalized and/or optionally being partially or fully fluorinated.
[0019] The remaining of the silicone polymer composition may include other polymers, fillers and additives.
[0020] In one embodiment, the silicone polymer composition comprises up to 90 % by weight of non-silicone polymers or co-polymers, fillers and/or additives.
[0021] The non-silicone polymers may e.g. be thermoplastics or thermosets, preferably selected from the group consisting of polyolefins, polyesters, polyurethanes, polycarbonates, polyvinyl polymers. In one embodiment the non-silicone polymers are selected from the group of polyamide, polyesters, polyether, polyethylene glycol, polysaccharide, cellulose, polyethylene, polypropylene, polybutylene, polyacrylonitrile, polyurethane, poly(vinyl chloride), poly(methyl methacrylate), polystyrene, polysulfone, polycarbonate, fluoropolymers such as polytetrafluoroethylene, polyvinyldifluoride, synthetic and natural rubber, thermoplastic elastomer, phenol-formaldehyde, melamine-formaldehyde, and urea-formaldehyde,-and mixtures thereof.
[0022] The fillers may e.g. be particles or fibres e.g. in the form of minerals or organic fillers, preferably selected from the group consisting of silica, metals, metal oxides, mixed metal oxides, glass beads or glass fibers. Other examples of fillers are those that are disclosed in US 5,968,652, US 2001/00366617, US 5,861,445 and US 4,740,538, and in the co-pending application filed simultaneously with this application by the same applicant.
[0023] The additives may e.g. be selected from the group consisting of adhesion promoters for 2K-constructions, process and plasticizing oils, antioxidants and pigments.
[0024] The silicone polymer composition may be partly or totally vulcanized. The vulcanization degree has influence on its swelling properties, and consequently a totally vulcanized silicone polymer composition may for some compositions be difficult to swell with the solvent carrying large monomers.
[0025] The silicone polymer composition may also deliberately be only partly vulcanized, such as below 98%, such as below 95%, in order to enlarge the "channels" or cavities in which reactive monomers are deposited.
[0026] In one embodiment, the silicone polymer composition is partially vulcanized, such as up to a vulcanization degree (cross-linking degree) of at least 50%, such as at least 70%, such as at least 90% or wholly, such as at least 96%, such as at least 97%, such as at least 98%.
[0028] The silicone polymer composition may preferably be at least partly transparent. In one embodiment, a transparent silicone polymer composition is loaded with monomer and e.g. peroxides and is thereafter subjected to an activation step e.g. heating for polymerization and cross-linking the monomers. The resulting product is of milky-white appearance, presumably due to a microstructure of small domains in size below or in the order of the wavelength of visible light, in addition due to different refractive indices of silicone versus monomer, and possibly due to the interpenetrating network structure formed, depending on the concentration of the monomer.
[0029] The monomer(s) should preferably be dissolvable or dispersable in the solvent at the exposing step. In one embodiment, the one or more monomers are dissolvable in the solvent, when the solvent is in liquid state, in gas state or in supercritical state. Preferably the one or more monomers are dissolvable in the solvent its liquid and/or supercritical state.
[0030] The monomers may in principle be any type of polymerizable monomers. Even relatively large monomers can be used, provided that they are dissolvable or dispersable in the solvent. Since the solvent has a low surface tension, it is capable of dissolving a large number of different types of monomers, also monomers that are difficult to dissolve in solvents used in prior art methods.
[0031] In one embodiment, the one or more monomers comprise at least 1 % by weight, such as at least 10 % by weight, such as at least 50 % by one or more of the monomers selected from the group consisting of silicon containing monomers such as silanes, such as TEOS (tetraethylorthosilicate or tetraethoxysilane) or chloro- or alkoxy-functional silanes, olefins such as ethylene, propylene, styrene, vinylpyrrolidone, oxygen- and nitrogen-containing monomers such as acrylic derivatives, e.g. acrylic ester and acrylic acid, methacrylic acid and -ester, urethanes, mono- and di-functional alcohols, carboxylic acids, amines, isocyanates, epoxides, aromatic compounds such as aromatics carrying substituents such as alkyl groups and sulfonated aromatics, aromatic resins, imidazol and imidazol derivatives, pyrazoles, quartenary ammonium compounds, polyurethane prepolymers and epoxy resins.
[0032] In one embodiment, it is preferred that the one or more monomers comprise at least 50 % by weight of vinylpyrrolidone.
[0033] In one embodiment, it is preferred that the one or more monomers comprise at least 50 % by weight of olefins.
[0034] In one embodiment, it is preferred that the one or more monomers comprise at least 50 % by weight of silanes.
[0035] For providing a simple polymerization step it is in one embodiment desired that the one or more monomers are free radical polymerizable. In another embodiment, the one or more monomers are polymerizable using irradiation e.g. using infrared radiation with a wavelength measured in vacuum of between 0.5 µm and 20 cm, such as between 0.8 µm and 10 cm, such as between 1.0 µm and 1 cm. In one embodiment, the cross-linking is activated by exposing the extruded polymer to electromagnetic waves with a wavelength measured in vacuum of between 2.0 µm and 1000 µm.
[0036] Together with the monomer and optionally radical starter, other additives such as pigments and proton-conducting components may be loaded into the silicone polymer composition.
[0037] These optional additives as well as optional radical starters may be loaded together with the monomer or they may be loaded separately.
[0038] The solvent and the exposing conditions should be selected such that the solvent has a surface tension at the exposing step of about 15 mN/m or less, such as about 10 mN/m or less, such as about 8 mN/m or less, such as about 6 mN/m or less, such as about 5 mN/m or less, such as about 0 mN/m.
[0039] Irrespectively of the state of the solvent during the exposing step, it is in one embodiment desired that the solvent has a surface tension in liquid form of about 15 mN/m or less, such as about 10 mN/m or less, such as about 8 mN/m or less, such as about 6 mN/m or less, such as about 5 mN/m or less. Thereby the monomers may be dissolved in the solvent in its liquid step prior to the exposing step.
[0040] The solvent may at the exposing step be in any of its states gas state, liquid state and supercritical state.
[0041] In one embodiment, the solvent is one or more hydrocarbons or carbon-containing compounds or a composition comprising hydrocarbons or carbon-containing compounds with a Hildebrand solubility of below 11, preferably 8 or less. In this embodiment the silicone polymer composition may preferably be exposed to the solvent in its supercritical state or near it supercritical state, where the term 'near its supercritical state' means that the total pressure is at least 10 bar.
[0042] In one embodiment, the solvent comprises one or more compounds from the group of C1-C12 hydrocarbons or carbon-containing compounds, preferably C1-C4 hydrocarbons, more preferably selected from the group consisting of methane, ethane, propane, propene, isobutane, butane, butene, isobutene, methanol, and acetone.
[0043] In one desired embodiment, the solvent comprises one or both of the compounds N2O and CO2. The most preferred solvent is a solvent comprising CO2.
[0044] In one embodiment, the solvent comprises at least 50 %, such as at least 75%, such as at least 90% by weight of one or more of the components selected from the group consisting of CO2, and N2O, and C1-C5 hydrocarbons, the solvent preferably comprising at least 50 %, such as at least 90% of CO2.
[0045] The solvent may also comprise a surfactant for reducing surface tension. In one embodiment, the solvent comprises a surfactant preferably selected from the group of anionic, cationic, non-ionic and amphoteric surfactants, said solvent preferably comprising up to 5% by weight, such as between 0.001-50 grams of surfactant per kg solvent.
[0046] In one embodiment, the pressure during the exposing step may preferably be well above 2 kg/cm2 such as at least 30 kg/cm2, such as at least 40 kg/cm2, such as between 40 and 500 kg/cm2 such as between 50 and 300 kg/cm2 such as between 60 and 200 kg/cm2, such as between 70 and 150 kg/cm2.
[0047] It should be understood that the pressure may vary during the exposing step e.g. so that the solvent (preferably comprising or even consisting essentially of CO2) is changing state from liquid to supercritical or vice versa during the exposing step. Such pressure regulation may in one embodiment result in an even faster dispersion and precipitation of the monomer(s).
[0048] The temperature at the exposing step may in one embodiment preferably be at least 0 °C, such as at least 10 °C, such as at least 10°C, such as between 15 and 120 °C, such as between 25 and 80 °C.
[0049] In one embodiment, the solvent consists essentially of CO2. The critical points of a carbon dioxide are about 31.0 °C and 75.3 kg/cm2, and it is referred to as being in a supercritical condition to be in the condition of having exceeded this and to have the in-between property of a liquid and a gas, i.e., the consistency near a liquid, and a diffusion coefficient near a gas. Moreover, although there is no clear definition, generally a subcritical state exists near the supercritical condition, i.e. about 50 kg/cm2 or more and in about 25 °C or more. In one embodiment, it is thus desired that the pressure and temperature is selected so that the CO2 is in its subcritical state during at least part of the exposing step.
[0050] For polymerizing and optionally cross-linking the monomer(s) it is in one embodiment desired that a radical starter in an amount preferably being sufficient to initiate the polymerization, is incorporated into the silicone polymer composition. This may be done prior to the vulcanization of the silicone polymer composition, or after the vulcanization e.g. simultaneously with the loading of the monomer(s) into the silicone polymer composition.
[0051] In one embodiment, a radical starter is incorporated into the silicone polymer by physical compounding e.g. prior to vulcanization thereof.
[0052] In one embodiment, a radical starter is incorporated into the silicone polymer by swelling or impregnation in dissolved condition, or by co-impregnation with the one or more monomers.
[0053] In one embodiment, one or more monomers are dissolved in the solvent together with a radical starter, and thereafter the solvent are swelled by the silicone polymer composition.
[0054] The amount of radical starter could e.g. be at least 0.01 mol % of the monomer, such as at least 0.01 mol % of the monomer, such as at least 0.1 mol % of the monomer, such as at least 0.5 mol % of the monomer, such as at least 1 mol % of the monomer, such as between 1 and 10 mol % of the monomer. The skilled person will for a specific combination of monomer(s) and radical starter be able to find a suitable amount of radical starter.
[0055] The radical starter may be any kind of radical starter, e.g. heat- or radiation activatable radical starters as known in the art. Suitable radical starters are e.g. peroxides such as dicumylperoxide or azo-compounds such as azo-bis-iso-butyronitril, or photo-labile compounds such as benzoyl-based radical starters, said radical starter preferably being.
[0056] As mentioned the silicone polymer composition may be exposed to the solvent while the solvent is in liquid state, in gas state and/or in supercritical state. The solvent may change state during the exposing step, e.g. by changing pressure and/or temperature. As it is simpler and faster to control the pressure, change of states during the exposing state is most often induced by adjusting the pressure.
[0057] In one embodiment, the silicone polymer composition is exposed to the solvent under conditions where the solvent is in a first state, followed by a change of conditions whereby the solvent changes to a second state, where the first state preferably is liquid state or supercritical state and the second state preferably is gas state.
[0058] In one embodiment, the monomer is dissolved in gas solvent, and the silicone polymer composition is exposed to the solvent while the solvent is in liquid state, in gas state and/or in supercritical state.
[0059] In one embodiment, the monomer is dissolved in supercritical solvent, and the silicone polymer composition is exposed to the solvent while the solvent is in liquid state, in gas state and/or in supercritical state.
[0060] The amount of solvent swelled by the silicone polymer composition may vary largely and is highly dependent on the silicone polymer composition and its vulcanization degree. Even if only small amounts are swelled, the solvent may transport sufficient monomers into the silicone polymer composition as the solvents may be mobile within the silicone polymer composition and pass in and out a number of times during the exposing step.
[0061] The exposing time may also vary depending on the desired amount of monomers to be loaded into the silicone polymer composition.
[0062] In one embodiment, the silicone polymer composition is exposed to said solvent for a sufficient time to swell the silicone polymer composition with the solvent, preferably to swell the silicone polymer composition with at least 0.01 %, such as at least 0.1 %, such as at least 1% by weight of solvent calculated on the weight of the silicone polymer composition.
[0063] In order to precipitate (load) as much as possible of the monomer(s) into the silicone polymer composition as fast as possible, the pressure and/or the temperature may be varied during the exposing step.
[0064] In one embodiment, wherein the silicone polymer composition is exposed to the solvent under varying pressure, the pressure preferably may be decreased after at least a part of the solvent has been swelled into the silicone polymer composition whereby monomer(s) precipitate within the silicone composition.
[0065] In one embodiment, wherein the silicone polymer composition is exposed to the solvent under varying temperature, the temperature preferably is decreased after at least part of the solvent has been swelled into the silicone polymer composition whereby monomer(s) precipitate within the silicone composition.
[0066] In one embodiment, the one or more monomers are exposed to the solvent for a sufficient time to precipitate at least 0.01 %, such as at least 0,1 %, such as at least 1 % by, such as up to about 50 % by weight of monomer(s) of the total weight of the silicone polymer composition.
[0067] The silicone polymer composition may in one embodiment be subjected to two or more exposing steps e.g. for increasing the amount of monomers loaded into the silicone polymer composition or for loading different monomers or other additives into the silicone polymer composition in a specified order.
[0068] In one embodiment, the silicone polymer composition is exposed in two or more steps to the solvent with one or more monomers to provide at total monomer precipitation of at least 0.01 %, such as at least 0.1 %, such as at least 1 % by, such as up to about 50 % by weight of monomer(s) of the total weight of the silicone polymer composition. The two or more steps may be equal to each other or they may be different from each other e.g. with respect to solvent, monomer amounts and/or exposing time.
[0069] Typical exposing time for the silicone polymer composition in total is normally within 20 min, such as at least 1 min, such as for 5 min. However, the invention does not exclude higher exposing times, such as exposing times up to several hours.
[0070] In one embodiment, it is desired that the solvent during at least part of the exposing time is in its supercritical state.
[0071] In one embodiment, the silicone polymer composition is subjected to an extraction step for extraction of silicone oil residues e.g. as disclosed in the co pending application PCT/DK/0300052 which is hereby incorporated by reference.
[0072] In one embodiment, the extraction solvent used in the extraction step is identical with the solvent used in the exposing step.
[0073] In one embodiment, the silicone polymer composition is treated with the solvent in or near its supercritical state for extracting residues followed by feeding of the monomer into the reaction chamber where the monomer is dissolved in the solvent in or near its supercritical state while the silicone polymer composition simultaneously is exposed to the solvent.
[0074] In one embodiment, the silicone polymer composition is exposed to a solvent consisting essentially of carbon dioxide. The CO2 is carrying the monomer(s) in or near its supercritical state for a sufficient time to swell the silicone polymer composition with the solvent containing the monomer(s).
[0075] The silicone polymer composition may preferably prior to the exposing step be shaped to the desired shape, e.g. using extrusion, injecting-moulding, calendering, pressing or cutting as it is well known in the art.
[0076] The IPNs produced using the method as disclosed above are useful as engineering materials for automotive switches and displays, telecom applications such as EMI shielding, gas separation membranes, membranes for fuel cells and carriers for heterogeneous catalysts.
[0077] The IPN produced according to the invention may further be suitable as general light spreading medium, e.g. as lamp cover.
[0078] The invention also relates to a method of producing a polymeric unit in particular suitable for automotive or telecom use. This method comprises the steps of producing an IPN as described above followed by a surface treatment e.g. by plasma or flame surface activation and subsequent painting, or immediate painting or coating.
[0079] The silicone polymer composition used for the IPN for automotive or telecom use may preferably be transparent. When using a transparent silicone polymer composition, the resulting product may as described above be of milky-white appearance, presumably due to a microstructure of small domains in size below or in the order of the wavelength of visible light, in addition due to different refractive indices of silicone versus monomer, and possibly due to the interpenetrating network structure formed, depending on the concentration of the monomer.
[0080] Such a resulting milky-white appearance is preferred for switches illuminated from the backside due to even spreading of light. Furthermore, danger of destroying the thin white paint layer by laser cutting or similar is reduced due to the thickness of the milky-white layer.
[0081] In this connection it should be observed that prior art silicone parts are used, e.g. as covers for switches such as steering wheel switches. Such prior art silicone parts are normally produced from transparent silicone applied with a thin white paint layer as well as a darker paint layer which is applied after a suitable surface activation process, e.g. plasma or flame treatment. Symbols are being cut through the dark paint layer using a laser. This way, the switch symbols can be illuminated from the inner side of the switch. Both surface activation and application of a thin paint layer of controlled thickness are, however, difficult, expensive and labor-intensive.
[0082] By using the method of the present invention, one painting step is avoided in typical white-plus-colour combinations designed for subsequent laser cutting of symbols.
[0083] In one embodiment, the impregnated reactive monomer is made adhesive to paint, e.g. by using styrene, acrylics, urethanes which can chemically add to reactive parts of the paint formulation. This way, plasma or other surface treatment prior to painting is avoided. This way, a cheap and technically improved route is opened.
[0084] The invention also relates to a method of producing a polymer membrane comprising the steps of:
- producing an IPN unit shaped as a membrane according to the disclosure above, wherein the membrane has a thickness between 5 and 1000 µm.
[0085] The amount of monomer precipitated into the membrane shaped silicone polymer composition is preferably 5 % by weight or less, such as 2% or less or such as 1% and less.
[0087] In one embodiment, the membrane is a fuel cell membrane. The membrane preferably is less permeable to gases than the original silicone composition at least by a factor of 2. Furthermore it is preferred that the conductivity for protons (H+) preferably is increased in comparison with the original silicone composition by incorporation of proton-conducting monomers such as imidazol or imidazol derivatives. The conductivity for protons (H+) preferably is increased in comparison with the original silicone composition by a factor of at least 10, such as at least 100.
[0088] A membrane for fuel cells obtained according to the present invention is relatively cheap, oxidation stable and has low tendency to dry out compared with prior art fuel cell membranes.
[0089] Silicone is highly oxidation stable. In advanced applications, fluorinated silicones or silicones carrying phenyl groups may preferably be used. Reactive monomers are chosen which preferably carry as little as possible tertiary H-atoms which are particularly prone to oxidation.
[0090] Furthermore, by using the present invention it is possible in a simple manner to produce a membrane that is selectively permeable (or conductive) to protons and hydroxide ions, respectively.
[0091] The danger of drying out (loss of water) does practically not exist in case imidazol derivatives or other proton carriers are used.
[0093] The danger of drying out (loss of water) does practically not exist in case imidazol derivatives or other proton carriers are used.
EXAMPLES
Example 1
Monomers:
[0095]
PEG (poly(ethylene glycol)) (Mw = 400)
PPG (poly(propylene glycol) (Mw = 425)
Poly(ethylene oxide-b-propylene oxide) 0.15:1 (Mw = 1100)
Poly(DSM-b-ethylene oxide) 20:80 (Mw = 3000)
[0096] The samples were made in laboratory scale equipment (reactor volume 5 - 1000ml, connected to gas supply, cylindrical inside, heated by a thermostat bath and stirred by a magnetic stirrer). Poly(dimethyl siloxane) (PDMS) rubber was used as substrate (silicone polymer composition).
[0097] A typical experiment was done as follows:
impregnation was completed, pressure was decompressed to atmospheric pressure, and the samples were post-cured for some hours to remove the whole carbon dioxide.
[0099] The surface tension was for all samples about 30 mN/m. The weight increase was between 0.75 and 1.25 % and FTIR spectra showed bonds at 2870 cm-1 (CH2, CH3) and 1348 cm-1 (C-O-C) beside the strong silicone bonds from the substrate.
[0100] Products of this type may e.g. be used as follows:
- Adhesion to e.g. PS, PP or PE is possible. Products produced as described may thus be used in situations where it should adhere to such polymers.
- PEG is biocompatible and the products using PEG as monomers are thus useful in life-science application
Example 2
White surface/bulk
[0102] The silicone substrate is as in example 1, and is treated in the same way as described above but with impregnation with both monomer and initiator. Furthermore, the post-curing step is made at high temperature to polymerize and to cross-link the monomer. The temperature is of about 80 °C and the sample is treated for 16 hrs. The result is milky-white silicone rubber with a surface tension of 22 mN/m. The weight increase is about 4% and the FTIR spectra shows the characteristic bonds of polystyrene (beside the strong bonds of the silicone substrate).
Example 3
Hydrophilic + white surface/bulk
[0103]
Substrate;
NVP (N-vinylpyrrolidone)
Monomer:
divinylbenzene
Initiator:
E.g. AIBN (azo-isobutyronitril)
[0104] The substrate is impregnated with monomer and initiator by a treatment similar to the treatment in example 1 above, but the post-curing step is made at high temperature to polymerize and to cross link the monomer. The temperature is of about 80 °C and the sample is treated for 16 hrs. The result is creamy-white silicone rubber with a surface tension of 35 mN/m. The weight increase is about 12 % and in the FTIR spectra a bond at 1670 cm-1 is the proof of the C=O bond of PVP.
Example 4
Hydrophilic + white surface/bulk
[0105]
Monomer:
PDMS impregnated with PS (polystyrene)
Monomer: NVP
Crosslinker: Divinylbenzene
Initiator: AIBN
[0106] The substrate, which already is impregnated with PS, is treated the same way as described in example 3 above. The result is a milky-white silicone rubber with a surface tension of 40 mN/m.
Example 5
Coloured surface/bulk
[0108] Added colours: red (perylenes; Oracet Red, Ciba, anthraquinone), blue (Victoria blue; Oracet Blue G, Ciba, phthalocyanine), green (brilliant green), yellow (Macolex Yellow 4G, Bayer Chemicals, Azo dyestuff; Oracet Yellow GHS, Ciba, anthraquinone)
[0109] Samples are made as described in the examples 1-4 above, but with the additional impregnation with one or more of the added colours and without polymerization in the post-curing step. Deepness of the final colour is dependent on the time of treatment but the transparency of the substrate is preserved.
Example 6
Automotive parts
[0111] A transparent silicone rubber is exposed to pressurized carbon dioxide which is able to extract volatile or low molecular weight residues from the rubber. At the same time (or later), a reactive monomer such as silanes such as TEOS, styrene, acrylic derivatives (such as acid or ester), vinylpyrrolidone, isocyanate or any other reactive monomer is introduced, dissolved in carbon dioxide. Optionally, a radical starter such as azo-bis-iso-butyronitril, peroxides or the like is added in small concentrations such as 1% of the reactive monomer. The reactive monomer is evenly distributed within the silicone rubber, such as at 4% wt. of the rubber. After removal of the solvent carbon dioxide, residual monomer can be recycled or discarded.
[0112] The polymer products are exposed to high temperature, e.g. in the same reactor which is used for carbon dioxide treatment, to let the reactive monomer polymerize.
[0113] The resulting product is of milky-white appearance, presumably due to a microstructure of small domains in size below or in the order of the wavelength of visible light, in addition due to different refractive indices of silicone versus monomer, and possibly due to the interpenetrating network structure formed, depending on the concentration of the monomer.
Example 7
Membranes for fuel cells
[0114] Manufacturing as described in example 6. The target membrane is not permeable to gases, but conductive for protons or hydroxide ions. In addition, good contact to porous, e.g. ceramic electrodes, is desired.
[0115] Useful monomers are silanes such as TEOS, styrene, aromatic compounds carrying groups which render the molecule less mobile and volatile, such as trialkyl-groups, optionally the aromatic core(s) being sulfonated or otherwise converted into acids, aromatic resins, typical known proton carriers such as imidazol derivatives, pyrazoles, quaternary ammonium compounds and various others.
[0116] The loading of silicone rubber with reactive monomer may be carried out more than once in order to achieve maximum loading, i.e. limited gas permeability.
Example 8
Gas separation membranes
[0117] A low degree of loading of reactive monomers, such as 0.1% weight of silicone, is chosen to modify thin tubes of silicone rubber. This way, the high gas permeability of silicone is preserved, however, the reactive monomer modifies the permeability of certain gases. Paraffinic impregnation, as one example, hinders the diffusion of paraffinic gases and allows the separation, e.g. of methane and oxygen.
Example 9
Water repellent membrane
[0118] To make a silicone substrate water repellent the pores in the bulk can be filled up with a hydrophobic compound like fluorpolymeres or paraffines using the method of the invention.
Example 10
Gas separation membrane
Impermeable to carbon dioxide or oxygen
[0119] Gas barrier membrane: IPN of silicone rubber with impregnated and crosslinked barrier compound: ethylvinyl alcohol, poly(vinylidene chloride), poly(vinylidene chloride-co-vinyl chloride.
[0120] The silicone substrate was impregnated with ethylvinyl alcohol, poly(vinylidene chloride), poly(vinylidene chloride-co-vinyl chloride e.g. as disclosed in example 2.
Example 11
Gas separation membrane
Impermeable to carbon dioxide or oxygen
[0121] Gas absorption: IPN of silicone rubber and an active compound which can react with CO2 to e.g. carbonate or hydrogen carbonate. The active compound could be an amine e.g. ethanolamine.
[0122] The silicone substrate was impregnated with ethanolamine and hydrogen carbonate using the method as disclosed in example 2.
Example 12
Gas separation membrane
Impermeable to hydrogen but permeable to H+
1. A method of producing an interpenetrating polymer network (IPN) comprising the steps
of
i) providing a silicone polymer composition,
ii) providing one or more monomers for a polymer,
iii) providing a solvent for the one or more monomers,
iv) exposing said silicone polymer composition to said one or more monomers and said solvent in liquid or supercritical state to precipitate monomer within said silicone polymer composition and
v) polymerizing said monomer to form an IPN,
wherein said solvent has a surface tension at the exposing step of about 15 mN/m or less.2. A method of producing an IPN according to claim 1, wherein said solvent has a surface
tension at the exposing step of about 5 mN/m or less.
3. A method of producing an IPN according to any one of the claims 1 and 2, wherein said
silicone polymer composition comprises at least 10 % by weight of polymer having a
backbone consisting of Si and O molecules.
4. A method of producing an IPN according to any one of the claims 1 and 2, wherein said
silicone polymer composition comprises at least 10 % by weight of polymer having a
backbone consisting of Si molecules.
5. A method of producing an IPN according to any one of the preceding claims, wherein
said silicone polymer composition comprises at least 10 by weight of polysiloxane
polymer.
6. A method of producing an IPN according to any one of the preceding claims, wherein
said silicone polymer composition comprises one or more polymers selected from the
group consisting of dimethyl polysiloxan, methylphenyl polysiloxane, fluorosilicone
rubber, silicone esters, polysiloxanes, polysilanes, chlorosilanes, alkoxysilanes,
aminosilanes, polysilanes polydialkylsiloxanes, polysiloxanes containing phenyl substituents,
said polymers of the silicone polymer composition optionally being vinyl-functionalized
and/or optionally being partially or fully fluorinated.
7. A method of producing an IPN according to any one of the preceding claims, wherein
said silicone polymer composition comprises up to 90 % by weight of non-silicone polymers
or co-polymers, fillers and/or additives, said non-silicone polymers is preferably
thermoplastics or thermosets selected from the group consisting of polyolefins, polyesters,
polyurethanes, polycarbonates, polyvinyl polymers, said fillers is preferably particles
or fibres selected from the group consisting of silica, metals, metal oxides, mixed
metal oxides, glass beads or glass fibers, and said additives is preferably selected
from the group consisting of adhesion promoters for 2K-constructions, process and
plasticizing oils, antioxidants and pigments.
8. A method of producing an IPN according to any one of the preceding claims, wherein
said silicone polymer composition is partially vulcanized to a vulcanization degree
(cross-linking degree) of at least 50 %.
9. A method of producing an IPN according to any one of the preceding claims, wherein
said silicone polymer composition is a vulcanized rubber.
10. A method of producing an IPN according to any one of the preceding claims, wherein
said one or more monomers are dissolvable in said solvent when said solvent is in
liquid state, in gas state or in supercritical state, said monomer preferable being
dissolvable in the solvent in its liquid and/or supercritical state.
11. A method of producing an IPN according to any one of the preceding claims, wherein
said one or more monomers comprise at least 1 % by weight of one or more of the monomers
selected from the group consisting of silicone containing monomers olefins, styrene,
vinylpyrrolidone, oxygen- and nitrogen-containing monomers, aromatic compounds, aromatic
resins, imidazol and imidazol derivatives, pyrazoles, quartenary ammonium compounds,
polyurethane prepolymers and epoxy resins.
12. A method of producing an IPN according to any one of the preceding claims 1-10, wherein
said one or more monomers comprise at least 50 % by weight of vinylpyrrolidone.
13. A method of producing an IPN according to any one of the preceding claims 1-10, wherein
said one or more monomers comprise at least 50 % by weight of olefins.
14. A method of producing an IPN according to any one of the preceding claims 1-10, wherein
said one or more monomers comprise at least 50 % by weight of silanes.
15. A method of producing an IPN according to any one of the preceding claims, wherein
said one or more monomers are free radical polymerizable.
16. A method of producing an IPN according to any one of the preceding claims, wherein
the solvent is one or more hydrocarbons or carbon-containing compounds or a composition
comprising hydrocarbons or carbon-containing compounds with a Hildebrand solubility
of below 11, preferably 8 or less, the silicone polymer composition preferably being
exposed to the solvent in its supercritical state or near it supercritical state,
where the term 'near its supercritical state' means that the total pressure is at
least 10 bar.
17. A method of producing an IPN according to any one of the preceding claims, wherein
the solvent comprises one or more compounds from the group of C1-C12 hydrocarbons or carbon-containing compounds, preferably C1-C4 hydrocarbons, more preferably selected from the group consisting of methane, ethane,
propane, propene, isobutane, butane, butene, isobutene, methanol, acetone, N2O and CO2, more preferably the solvent comprises CO2, the silicone polymer composition being exposed to the solvent in supercritical state.
18. A method of producing an IPN according to any one of the preceding claims, wherein
the solvent has a surface tension in liquid form of about 15 mN/m or less, the silicone
polymer composition being exposed to the solvent while it is in one or more of its
states liquid state, gas state and supercritical state.
19. A method of producing an IPN according to claim 18, wherein said solvent comprises
at least 50 % by weight of one or more of the components selected from the group consisting
of CO2, and N2O, and C1-C5 hydrocarbons, the solvent preferably comprising at least 50 % by weight of CO2.
20. A method of producing an IPN according to any one of the preceding claims, wherein
the solvent comprises a surfactant, said solvent preferably comprising up to 5 % by
weight.
21. A method of producing an IPN according to any one of the preceding claims, wherein
a radical starter is incorporated into said silicone polymer, preferably by physical
compounding, by swelling or impregnation in dissolved condition, or by co-impregnation
with the one or more monomers, the amount of radical starter preferably being sufficient
to initiate the polymerization.
22. A method of producing an IPN according to any one of the preceding claims, wherein
said one or more monomers are dissolved in the solvent together with a radical starter,
the amount of radical starter preferably being sufficient to initiate the polymerization.
23. A method of producing an IPN according to any one of the claims 21 and 22, wherein
the amount of radical starter is at least 0.01 mol % of the monomer.
24. A method of producing an IPN according to any one of the preceding claims 21-23, wherein
said radical starter is selected from the group consisting of peroxides, said radical
starter preferably being heat- or radiation activatable.
25. A method of producing an IPN according to any one of the preceding claims, wherein
said monomer is dissolved in liquid solvent, said silicone polymer composition being
exposed to said solvent while the solvent is in liquid state, in gas state and/or
in supercritical state.
26. A method of producing an IPN according to any one of the preceding claims 1-24, wherein
said monomer is dissolved in gas solvent, said silicone polymer composition being
exposed to said solvent while the solvent is in liquid state, in gas state and/or
in supercritical state.
27. A method of producing an IPN according to any one of the preceding claims 1-24, wherein
said monomer is dissolved in supercritical solvent, said silicone polymer composition
being exposed to said solvent while the solvent is in liquid state, in gas state and/or
in supercritical state.
28. A method of producing an IPN according to any one of the preceding claims, wherein
said silicone polymer composition is exposed to said solvent for a sufficient time
to swell the silicone polymer composition with the solvent, preferably to swell the
silicone polymer composition with at least 0.01 % by weight of solvent calculated
on the weight of the silicone polymer composition.
29. A method of producing an IPN according to any one of the preceding claims, wherein
said silicone polymer composition is exposed to said solvent under varying pressure,
the pressure being decreased after at least part of the solvent has been swelled into
the silicone polymer composition whereby monomer(s) precipitate within the silicone
composition.
30. A method of producing an IPN according to any one of the preceding claims, wherein
said silicone polymer composition is exposed to said solvent under varying temperature,
the temperature being decreased after at least part of the solvent has been swelled
into the silicone polymer composition whereby monomer(s) precipitate within the silicone
composition.
31. A method of producing an IPN according to any one of the preceding claims, wherein
said silicone polymer composition is exposed to said solvent under conditions where
the solvent is in a first state, followed by a change of conditions whereby the solvent
changes to a second state, said first state preferably being liquid state or supercritical
state and said second state preferably being gas state.
32. A method of producing an IPN according to any one of the preceding claims, wherein
said silicone polymer composition is exposed to said solvent with said one or more
monomers for a sufficient time to precipitate at least 0.01 % and up to about 50 %
by weight of monomer(s) of the total weight of the silicone polymer composition.
33. A method of producing an IPN according to any one of the preceding claims, wherein
said silicone polymer composition is exposed in two or more steps to said solvent
with one or more monomers to provide at total monomer precipitation of at least 0.01
% and up to about 50 % by weight of monomer(s) of the total weight of the silicone
polymer composition.
34. A method of producing an IPN according to any one of the preceding claims 31 and 32,
wherein said silicone polymer composition is exposed to said solvent with said one
or more monomers for a total time of at least 1 min.
35. A method of producing an IPN according to any one of the preceding claims 1-16, wherein
said silicone polymer composition is treated with the solvent in or near its supercritical
state for extracting residues followed by feeding of the monomer into the reaction
chamber where the monomer is dissolved in the solvent in or near its supercritical
state while the silicone polymer composition simultaneously is exposed to the solvent.
36. A method of producing an IPN according to any one of the preceding claims, wherein
said silicone polymer composition is exposed to a solvent consisting essentially of
carbon dioxide and carrying the monomer(s) in or near its supercritical state, for
a sufficient time to swell the silicone polymer composition with the solvent with
monomer(s).
37. A method of producing an IPN according to any one of the preceding claims, wherein
said silicone polymer composition prior to the exposing step is shaped, preferably
by extrusion, injecting-moulding, calendaring, pressing or cutting.
38. A method of producing a polymeric unit comprising the steps of:
- producing an IPN unit in the desired shape according to any one of the preceding claims 1-37, and
- treating the surface thereof by plasma or flame surface activation and subsequent painting, or immediate painting or coating.
39. A method of producing a polymeric unit according to claim 38 wherein the silicone
polymer composition used for the IPN is transparent.
40. A method of producing a polymer unit according to any one of the claims 38 and 39,
wherein the one or more monomers comprise one or more from the group of styrene, acrylics
and urethanes
41. A method of producing a polymer membrane comprising the steps of:
- producing an IPN unit shaped as a membrane according to any one of the preceding claims 1-37, wherein the membrane has a thickness between 5 and 1000 µm.
42. A method of producing a polymer membrane according to claim 41 wherein the amount
of monomer precipitated into the silicone polymer composition is 5 % by weight or
less.
43. A method of producing a polymer membrane according to any one of the claims 41 and
42, wherein the membrane is a membrane for separation of gases or liquids.
44. A method of producing a polymer membrane according to any one of the claims 41 and
42, wherein the membrane is a fuel cell membrane, said membrane preferably being less
permeable to gases than the original silicone composition at least by a factor of
2, and whereby the conductivity for protons (H+) preferably is increased in comparison
with the original silicone composition by incorporation of proton-conducting monomers
such as imidazol or imidazol derivatives, the conductivity for protons (H+) preferably
being increased in comparison with the original silicone composition by a factor of
at least 10.
1. Verfahren zur Herstellung eines interpenetrierenden Polymernetzwerks (IPN), umfassend
die Schritte, dass
i) eine Silikonpolymerzusammensetzung bereitgestellt wird,
ii) ein oder mehrere Monomere für ein Polymer bereitgestellt werden,
iii) ein Lösungsmittel für das eine oder die mehreren Monomere bereitgestellt wird,
iv) die Silikonpolymerzusammensetzung dem einen oder den mehreren Monomeren und dem Lösungsmittel in flüssigem oder superkritischem Zustand ausgesetzt wird, um das Monomer in der Silikonpolymerzusammensetzung auszufällen;
v) das Monomer polymerisiert wird, um ein IPN zu bilden,
wobei das Lösungsmittel bei dem Aussetzungsschritt eine Oberflächenspannung von etwa 15 mN/m oder weniger hat.2. Verfahren zur Herstellung eines IPN nach Anspruch 1, wobei das Lösungsmittel bei dem
Aussetzungsschritt eine Oberflächenspannung von etwa 5 mN/m oder weniger hat.
3. Verfahren zur Herstellung eines IPN nach einem der Ansprüche 1 und 2, wobei die Silikonpolymerzusammensetzung
mindestens 10 Gew.-% Polymer aufweist, das ein Grundgerüst hat, das aus Si- und O-Molekülen
besteht.
4. Verfahren zur Herstellung eines IPN nach einem der Ansprüche 1 und 2, wobei die Silikonpolymerzusammensetzung
mindestens 10 Gew.-% Polymer aufweist, das ein Grundgerüst hat, das aus Si-Molekülen
besteht.
5. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
die Silikonpolymerzusammensetzung mindestens 10 Gew.-% Polysiloxanpolymer aufweist.
6. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
die Silikonpolymerzusammensetzung ein oder mehrere Polymere aufweist, ausgewählt aus
der Gruppe bestehend aus Dimethylpolysiloxan, Methylphenylpolysiloxan, Fluorsilikonkautschuk,
Silikonestern, Polysiloxanen, Polysilanen, Chlorsilanen, Alkoxysilanen, Aminosilanen,
Polysilane-Polydialkylsiloxanen, Polysiloxanen mit Phenylsubstituenten, wobei die
Polymere der Silikonpolymerzusammensetzung gegebenenfalls vinylfunktionalisiert und/oder
gegebenenfalls teilweise oder vollständig fluoriert sind.
7. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
die Silikonpolymerzusammensetzung bis zu 90 Gew.-% nicht-Silikonpolymere oder Copolymere,
Füllstoffe und/oder Additive aufweist, wobei die nicht-Silikonpolymere vorzugsweise
Thermoplaste oder Duroplaste sind, ausgewählt aus der Gruppe bestehend aus Polyolefinen,
Polyestern, Polyurethanen, Polycarbonaten, Polyvinylpolymeren, wobei die Füllstoffe
vorzugsweise Partikel oder Fasern sind, ausgewählt aus der Gruppe bestehend aus Siliciumdioxid,
Metallen, Metalloxiden, Mischmetalloxiden, Glasperlen oder Glasfasern, und wobei die
Additive vorzugsweise ausgewählt werden aus der Gruppe bestehend aus Haftvermittlern
für 2K-Konstruktionen, Prozess- und Plastifizierungsölen, Antioxidantien und Pigmenten.
8. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
die Silikonpolymerzusammensetzung bis zu einem Vulkanisationsgrad (Vernetzungsgrad)
von mindestens 50% teilweise vulkanisiert wird.
9. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
die Silikonpolymerzusammensetzung ein vulkanisierter Kautschuk ist.
10. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
das eine oder die mehreren Monomere in dem Lösungsmittel löslich sind, wenn das Lösungsmittel
in flüssigem Zustand, im Gaszustand oder in überkritischem Zustand vorliegt, wobei
das Monomer bevorzugt im Lösungsmittel in seinem flüssigen und/oder überkritischen
Zustand löslich ist.
11. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
das eine oder die mehreren Monomere mindestens 1 Gew.-% eines oder mehrerer der Monomere
aufweist, ausgewählt aus der Gruppe bestehend aus Silikon-haltigen Monomer-Olefinen,
Styrol, Vinylpyrrolidon, Sauerstoff- und Stickstoff-haltigen Monomeren, aromatischen
Verbindungen, aromatischen Harzen, Imidazol und Imidazolderivaten, Pyrazolen, quartären
Ammoniumverbindungen, Polyurethanpräpolymeren und Epoxidharzen.
12. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche 1 bis
10, wobei das eine oder die mehreren Monomere mindestens 50 Gew.-% Vinylpyrrolidon
aufweisen.
13. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche 1 bis
10, wobei das eine oder die mehreren Monomere mindestens 50 Gew.-% Olefine aufweisen.
14. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche 1 bis
10, wobei das eine oder die mehreren Monomere mindestens 50 Gew.-% Silane aufweisen.
15. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
das eine oder die mehreren Monomere radikalisch polymerisierbar sind.
16. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
das Lösungsmittel ein oder mehrere Kohlenwasserstoffe oder Kohlenstoff-haltige Verbindungen
oder eine Zusammensetzung ist, die Kohlenwasserstoffe oder Kohlenstoff-haltige Verbindungen
mit einer Hildebrand-Löslichkeit von unter 11, vorzugsweise 8 oder weniger, aufweist,
wobei die Silikonpolymerzusammensetzung vorzugsweise dem Lösungsmittel in seinem überkritischen
Zustand oder nahe seinem überkritischen Zustand ausgesetzt wird, wobei der Begriff
"nahe seinem überkritischen Zustand" bedeutet, dass der Gesamtdruck mindestens 10
bar beträgt.
17. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
das Lösungsmittel eine oder mehrere Verbindungen aus der Gruppe der C1-C12-Kohlenwasserstoffe oder Kohlenstoff-haltigen Verbindungen, vorzugsweise C1-C4-Kohlenwasserstoffe, besonders bevorzugt ausgewählt aus der Gruppe bestehend aus Methan,
Ethan, Propan, Propen, Isobutan, Butan, Buten, Isobuten, Methanol, Aceton, N2O und CO2, aufweist, wobei besonders bevorzugt das Lösungsmittel CO2 aufweist, wobei die Silikonpolymerzusammensetzung dem Lösungsmittel in überkritischem
Zustand ausgesetzt wird.
18. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
das Lösungsmittel eine Oberflächenspannung in flüssiger Form von etwa 15 mN/m oder
weniger hat, wobei die Silikonpolymerzusammensetzung dem Lösungsmittel ausgesetzt
wird, während es in einem oder mehrerer seiner Zustände; flüssiger Zustand, Gaszustand
und überkritischer Zustand; vorliegt.
19. Verfahren zur Herstellung eines IPN nach Anspruch 18, wobei das Lösungsmittel mindestens
50 Gew.-% einer oder mehrerer der Komponenten ausgewählt aus der Gruppe bestehend
aus CO2, und N2O, und C1-C5-Kohlenwasserstoffen aufweist, wobei vorzugsweise das Lösungsmittel mindestens 50
Gew.-% CO2 aufweist.
20. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
das Lösungsmittel ein Tensid aufweist, wobei das Lösungsmittel vorzugsweise bis zu
5 Gew.-% aufweist.
21. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
ein Radikalstarter in das Silikonpolymer eingebaut wird, vorzugsweise durch physikalische
Compoundierung, durch Quellen oder Imprägnierung im gelösten Zustand, oder durch Co-Imprägnierung
mit dem einen oder mehreren Monomeren, wobei die Menge an Radikalstarter vorzugsweise
ausreicht, um die Polymerisation einzuleiten.
22. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
das eine oder die mehreren Monomere in dem Lösungsmittel zusammen mit einem Radikalstarter
gelöst werden, wobei die Menge an Radikalstarter vorzugsweise ausreicht, um die Polymerisation
einzuleiten.
23. Verfahren zur Herstellung eines IPN nach einem der Ansprüche 21 und 22, wobei die
Menge an Radikalstarter mindestens 0,01 Mol-% des Monomers beträgt.
24. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche 21 bis
23, wobei der Radikalstarter ausgewählt wird aus der Gruppe bestehend aus Peroxiden,
wobei der Radikalstarter vorzugsweise wärme- oder strahlungsaktivierbar ist.
25. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
das Monomer in einem flüssigen Lösungsmittel gelöst wird, wobei die Silikonpolymerzusammensetzung
dem Lösungsmittel ausgesetzt wird, während das Lösungsmittel in flüssigem Zustand,
im Gaszustand und/oder im überkritischen Zustand vorliegt.
26. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche 1 bis
24, wobei das Monomer in einem Gaslösungsmittel gelöst wird, wobei die Silikonpolymerzusammensetzung
dem Lösungsmittel ausgesetzt wird, während das Lösungsmittel in flüssigem Zustand,
im Gaszustand und/oder im überkritischen Zustand vorliegt.
27. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche 1 bis
24, wobei das Monomer in einem überkritischen Lösungsmittel gelöst wird, wobei die
Silikonpolymerzusammensetzung dem Lösungsmittel ausgesetzt wird, während das Lösungsmittel
in flüssigem Zustand, im Gaszustand und/oder im überkritischen Zustand vorliegt.
28. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
die Silikonpolymerzusammensetzung dem Lösungsmittel für eine ausreichende Zeitdauer
ausgesetzt wird, um die Silikonpolymerzusammensetzung mit dem Lösungsmittel quellen
zu lassen, vorzugsweise um die Silikonpolymerzusammensetzung mit mindestens 0,01 Lösungsmittelgew.-%
bezogen auf das Gewicht der Silikonpolymerzusammensetzung quellen zu lassen.
29. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
die Silikonpolymerzusammensetzung dem Lösungsmittel unter variierendem Druck ausgesetzt
wird, wobei der Druck verringert wird, nachdem mindestens ein Teil des Lösungsmittels
in die Silikonpolymerzusammensetzung gequollen wurde, wodurch Monomer(e) in der Silikonzusammensetzung
ausfallen.
30. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
die Silikonpolymerzusammensetzung dem Lösungsmittel unter variierender Temperatur
ausgesetzt wird, wobei die Temperatur verringert wird, nachdem mindestens ein Teil
des Lösungsmittels in die Silikonpolymerzusammensetzung gequollen wurde, wodurch Monomer(e)
in der Silikonzusammensetzung ausfallen.
31. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
die Silikonpolymerzusammensetzung dem Lösungsmittel unter Bedingungen ausgesetzt wird,
in denen sich das Lösungsmittel in einem ersten Zustand befindet, gefolgt von einer
Änderung der Bedingungen, wodurch das Lösungsmittel zu einem zweiten Zustand wechselt,
wobei der erste Zustand vorzugsweise flüssiger Zustand oder überkritischer Zustand
ist, und der zweite Zustand vorzugsweise Gaszustand ist.
32. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
die Silikonpolymerzusammensetzung dem Lösungsmittel mit dem einen oder den mehreren
Monomeren für eine ausreichende Zeit ausgesetzt wird, um mindestens 0,01 Gew.-% und
bis zu etwa 50 Gew.-% des Monomers (der Monomere) des Gesamtgewichts der Silikonpolymerzusammensetzung
auszufällen.
33. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
die Silikonpolymerzusammensetzung in zwei oder mehr Schritten dem Lösungsmittel mit
einem oder mehreren Monomeren ausgesetzt wird, um für eine Gesamtmonomerausfällung
von mindestens 0,01 Gew.-% und bis zu etwa 50 Gew.-% des Monomers (der Monomere) des
Gesamtgewichts der Silikonpolymerzusammensetzung zu sorgen.
34. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche 31 und
32, wobei die Silikonpolymerzusammensetzung dem Lösungsmittel mit einem oder mehreren
Monomeren für eine Gesamtzeit von mindestens 1 min ausgesetzt wird.
35. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche 1-16,
wobei die Silikonpolymerzusammensetzung mit dem Lösungsmittel in oder nahe seinem
überkritischen Zustand zur Extraktion von Rückständen behandelt wird, gefolgt von
der Zuführung des Monomers in die Reaktionskammer, wo das Monomer in dem Lösungsmittel
in oder nahe seinem überkritischen Zustand gelöst wird, während die Silikonpolymerzusammensetzung
gleichzeitig dem Lösungsmittel ausgesetzt wird.
36. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
die Silikonpolymerzusammensetzung einem Lösungsmittel ausgesetzt wird, das im Wesentlichen
aus Kohlendioxid besteht und das das (die) Monomer(e) in oder nahe seinem überkritischen
Zustand für eine ausreichende Zeit trägt um die Silikonpolymerzusammensetzung mit
dem Lösungsmittel mit Monomer(en) quellen zu lassen.
37. Verfahren zur Herstellung eines IPN nach einem der vorhergehenden Ansprüche, wobei
die Silikonpolymerzusammensetzung vor dem Aussetzungsschritt geformt wird, vorzugsweise
durch Extrudieren, Spritzgießen, Kalandrieren, Pressen oder Schneiden.
38. Verfahren zur Herstellung einer polymeren Einheit, umfassend die Schritte:
- Herstellen einer IPN-Einheit in der gewünschten Form nach einem der vorhergehenden Ansprüche 1-37, und
- Behandeln ihrer Oberfläche durch Plasma- oder Flammenoberflächenaktivierung und anschließendes Lackieren, oder durch sofortiges Lackieren oder Beschichten.
39. Verfahren zur Herstellung einer Polymereinheit nach Anspruch 38, wobei die für das
IPN verwendete Silikonpolymerzusammensetzung transparent ist.
40. Verfahren zur Herstellung einer Polymereinheit nach einem der Ansprüche 38 und 39,
wobei das eine oder die mehreren Monomere ein oder mehrere aus der Gruppe Styrol,
Acryle und Urethane aufweisen.
41. Verfahren zur Herstellung einer Polymermembran, umfassend die Schritte:
- Herstellen einer als Membran geformten IPN-Einheit nach einem der vorhergehenden Ansprüche 1-37, wobei die Membran eine Dicke zwischen 5 und 1000 µm hat.
42. Verfahren zur Herstellung einer Polymermembran nach Anspruch 41, wobei die Menge an
in die Silikonpolymerzusammensetzung ausgefälltem Monomer 5 Gew.-% oder weniger beträgt.
43. Verfahren zur Herstellung einer Polymermembran nach einem der Ansprüche 41 und 42,
wobei die Membran eine Membran zur Trennung von Gasen oder Flüssigkeiten ist.
44. Verfahren zur Herstellung einer Polymermembran nach einem der Ansprüche 41 und 42,
wobei die Membran eine Brennstoffzellenmembran ist, die vorzugsweise mindestens um
den Faktor 2 weniger gasdurchlässig ist als die ursprüngliche Silikonzusammensetzung,
und wobei die Leitfähigkeit für Protonen (H+) im Vergleich zur ursprünglichen Silikonzusammensetzung
durch den Einbau von protonenleitenden Monomeren wie etwa Imidazol oder Imidazolderivaten
erhöht ist, wobei die Leitfähigkeit für Protonen (H+) vorzugsweise im Vergleich zur
ursprünglichen Silikonzusammensetzung um einen Faktor von mindestens 10 erhöht ist.
1. Procédé de production d'un réseau polymère à interpénétration (IPN), comprenant les
étapes consistant à :
i) fournir une composition polymère siliconée,
ii) fournir un ou plusieurs monomères pour un polymère,
iii) fournir un solvant pour les un ou plusieurs monomères,
iv) exposer ladite composition polymère siliconée auxdits un ou plusieurs monomères et audit solvant à l'état liquide ou supercritique afin de précipiter le monomère à l'intérieur de ladite composition polymère siliconée et
v) polymériser ledit monomère pour former un IPN,
dans lequel ledit solvant a une tension de surface à l'étape d'exposition d'environ 15 mN/m ou moins.2. Procédé de production d'un IPN selon la revendication 1, dans lequel ledit solvant
a une tension de surface à l'étape d'exposition d'environ 5 mN/m ou moins.
3. Procédé de production d'un IPN selon l'une quelconque des revendications 1 et 2, dans
lequel ladite composition polymère siliconée comprend au moins 10 % en poids de polymère
ayant un squelette constitué de molécules de Si et de 0.
4. Procédé de production d'un IPN selon l'une quelconque des revendications 1 et 2, dans
lequel ladite composition polymère siliconée comprend au moins 10 % en poids de polymère
ayant un squelette constitué de molécules de Si.
5. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel ladite composition polymère siliconée comprend au moins 10 % en poids
de polymère de polysiloxane.
6. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel ladite composition polymère siliconée comprend un ou plusieurs polymères
choisis dans le groupe constitué du diméthylpolysiloxane, du méthylphénylpolysiloxane,
du caoutchouc fluorosiliconé, des esters de silicone, des polysiloxanes, des polysilanes,
des chlorosilanes, des alcoxysilanes, des aminosilanes, des polysilanes polydialkylsiloxanes,
des polysiloxanes contenant des substituants phényliques, lesdits polymères de la
composition polymère siliconée étant éventuellement fonctionnalisés par un groupe
vinyle et/ou étant éventuellement partiellement ou entièrement fluorés.
7. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel ladite composition polymère siliconée comprend jusqu'à 90 % en poids de
polymères ou co-polymères non siliconés, de charges et/ou d'additifs, lesdits polymères
non siliconés étant de préférence des thermoplastiques ou des thermodurcissables choisis
dans le groupe constitué des polyoléfines, des polyesters, des polyuréthanes, des
polycarbonates, des polymères de polyvinyle, lesdites charges étant de préférence
des particules ou des fibres choisies dans le groupe constitué de la silice, des métaux,
des oxydes métalliques, des oxydes métalliques mixtes, des billes de verre ou des
fibres de verre, et lesdits additifs étant de préférence choisis dans le groupe constitué
des promoteurs d'adhésion pour les constructions 2K, des huiles de procédé et des
huiles plastifiantes, des antioxydants et des pigments.
8. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel ladite composition polymère siliconée est partiellement vulcanisée à un
degré de vulcanisation (degré de réticulation) d'au moins 50 %.
9. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel ladite composition polymère siliconée est un caoutchouc vulcanisé.
10. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel lesdits un ou plusieurs monomères peuvent être dissous dans ledit solvant
quand ledit solvant est à l'état liquide, à l'état gazeux ou à l'état supercritique,
ledit monomère préférable étant soluble dans le solvant à l'état liquide et/ou à l'état
supercritique.
11. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel lesdits un ou plusieurs monomères comprennent au moins 1 % en poids d'un
ou de plusieurs des monomères choisis dans le groupe constitué des monomères d'oléfines
contenant de la silicone, du styrène, la vinylpyrrolidone, des monomères contenant
de l'oxygène et de l'azote, des composés aromatiques, des résines aromatiques, de
l'imidazole et des dérivés d'imidazole, des pyrazoles, des composés d'ammonium quaternaire,
des prépolymères de polyuréthane et des résines époxy.
12. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes
1 à 10, dans lequel lesdits un ou plusieurs monomères comprennent au moins 50 % en
poids de vinylpyrrolidone.
13. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes
1 à 10, dans lequel lesdits un ou plusieurs monomères comprennent au moins 50 % en
poids d'oléfines.
14. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes
1 à 10, dans lequel lesdits un ou plusieurs monomères comprennent au moins 50 % en
poids de silanes.
15. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel lesdits un ou plusieurs monomères sont polymérisables par voie radicalaire.
16. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel le solvant est un ou plusieurs hydrocarbures ou composés contenant du
carbone ou une composition comprenant des hydrocarbures ou des composés contenant
du carbone avec une solubilité de Hildebrand inférieure à 11, de préférence de 8 ou
moins, la composition polymère siliconée étant de préférence exposée au solvant à
l'état supercritique ou proche de l'état supercritique, où le terme « proche de l'état
supercritique » signifie que la pression totale est d'au moins 10 bar.
17. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel le solvant comprend un ou plusieurs composés provenant du groupe des hydrocarbures
en C1 à C12 ou des composés contenant du carbone, de préférence des hydrocarbures en C1 à C4, plus préférentiellement choisis dans le groupe constitué du méthane, de l'éthane,
du propane, du propène, de l'isobutane, du butane, du butène, de l'isobutène, du méthanol,
de l'acétone, du N2O et du CO2, plus préférentiellement le solvant comprend du CO2, la composition polymère siliconée étant exposée au solvant à l'état supercritique.
18. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel le solvant a une tension de surface sous forme liquide d'environ 15 mN/m
ou moins, la composition polymère siliconée étant exposée au solvant alors qu'il se
trouve dans un ou plusieurs de ses états liquide, gazeux et supercritique.
19. Procédé de production d'un IPN selon la revendication 18, dans lequel ledit solvant
comprend au moins 50 % en poids d'un ou de plusieurs des composants choisis dans le
groupe constitué du CO2, et du N2O, et des hydrocarbures en C1 à C5, le solvant comprenant de préférence au moins 50 % en poids de CO2.
20. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel le solvant comprend un tensioactif, ledit solvant comprenant de préférence
jusqu'à 5 % en poids.
21. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel un initiateur radicalaire est incorporé dans ledit polymère siliconé,
de préférence par compoundage physique, par gonflement ou imprégnation à l'état dissous,
ou par co-imprégnation avec un ou plusieurs monomères, la quantité d'initiateur radicalaire
étant de préférence suffisante pour initier la polymérisation.
22. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel lesdits un ou plusieurs monomères sont dissous dans le solvant conjointement
avec un initiateur radicalaire, la quantité d'initiateur radicalaire étant de préférence
suffisante pour initier la polymérisation.
23. Procédé de production d'un IPN selon l'une quelconque des revendications 21 et 22,
dans lequel la quantité d'initiateur radicalaire est d'au moins 0,01 % en moles de
monomère.
24. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes
21 à 23, dans lequel l'initiateur radicalaire est choisi dans le groupe constitué
des peroxydes, ledit initiateur radicalaire étant de préférence activable par la chaleur
ou le rayonnement.
25. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel ledit monomère est dissous dans un solvant liquide, ladite composition
polymère siliconée étant exposée audit solvant alors que le solvant est à l'état liquide,
gazeux et/ou supercritique.
26. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes
1 à 24, dans lequel ledit monomère est dissous dans un solvant gazeux, ladite composition
polymère siliconée étant exposée audit solvant alors que le solvant est à l'état liquide,
gazeux et/ou supercritique.
27. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes
1 à 24, dans lequel ledit monomère est dissous dans un solvant supercritique, ladite
composition polymère siliconée étant exposée audit solvant alors que le solvant est
à l'état liquide, gazeux et/ou supercritique.
28. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel ladite composition polymère siliconée est exposée audit solvant pendant
une durée suffisante pour que la composition polymère siliconée gonfle avec le solvant,
de préférence pour que la composition polymère siliconée gonfle avec au moins 0,01
% en poids de solvant calculé sur le poids de la composition polymère siliconée.
29. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel ladite composition polymère siliconée est exposée audit solvant sous pression
variable, la pression étant réduite après qu'au moins une partie du solvant ait subi
un gonflement dans la composition polymère siliconée, moyennant quoi le ou les monomères
se précipitent à l'intérieur de la composition siliconée.
30. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel ladite composition polymère siliconée est exposée audit solvant sous température
variable, la température étant réduite après qu'au moins une partie du solvant ait
subi un gonflement dans la composition polymère siliconée, moyennant quoi le ou les
monomères se précipitent à l'intérieur de la composition siliconée.
31. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel ladite composition polymère siliconée est exposée audit solvant dans des
conditions où le solvant se trouve dans un premier état, suivi par un changement d'état,
moyennant quoi le solvant passe dans un deuxième état, ledit premier état étant de
préférence l'état liquide ou supercritique et ledit deuxième état étant de préférence
l'état gazeux.
32. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel ladite composition polymère siliconée est exposée audit solvant avec un
ou plusieurs monomères pendant une durée suffisante pour précipiter au moins 0,01
% et jusqu'à environ 50 % en poids d'un ou des monomères par rapport au poids total
de la composition polymère siliconée.
33. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel ladite composition polymère siliconée est exposée audit solvant en deux
étapes ou plus avec un ou plusieurs monomères afin de provoquer une précipitation
du monomère totale d'au moins 0,01 % et jusqu'à environ 50 % en poids d'un ou des
monomères par rapport au poids total de la composition polymère siliconée.
34. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes
31 et 32, dans lequel ladite composition polymère siliconée est exposée audit solvant
avec un ou plusieurs monomères pendant une durée totale d'au moins 1 min.
35. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes
1 à 16, dans lequel ladite composition polymère siliconée est traitée avec le solvant
à l'état supercritique ou proche de l'état supercritique pour l'extraction des résidus,
puis le monomère est chargé dans la chambre de réaction où le monomère est dissous
dans le solvant à l'état supercritique ou proche de l'état supercritique alors que
la composition polymère siliconée est simultanément exposée au solvant.
36. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel ladite composition polymère siliconée est exposée à un solvant se composant
essentiellement de dioxyde de carbone et portant le ou les monomères à l'état supercritique
ou proche de l'état supercritique pendant une durée suffisante pour que la composition
polymère siliconée gonfle avec le solvant avec le ou les monomères.
37. Procédé de production d'un IPN selon l'une quelconque des revendications précédentes,
dans lequel ladite composition polymère siliconée avant l'étape d'exposition est façonnée,
de préférence par extrusion, moulage par injection, calandrage, pressage ou coupage.
38. Procédé de production d'une unité polymérique comprenant les étapes consistant à :
- produire une unité d'IPN en la forme désirée selon l'une quelconque des revendications précédentes 1 à 37, et
- traiter la surface de celle-ci par plasma ou activation de surface à la flamme et peinture consécutive ou peinture immédiate ou revêtement.
39. Procédé de production d'une unité polymérique selon la revendication 38, dans lequel
la composition polymère siliconée utilisée pour l'IPN est transparente.
40. Procédé de production d'une unité polymérique selon l'une quelconque des revendications
38 et 39, dans lequel les un ou plusieurs monomères comprennent un ou plusieurs éléments
provenant du groupe du styrène, des acryliques et des uréthanes.
41. Procédé de production d'une membrane polymère comprenant les étapes consistant à :
- produire une unité d'IPN façonnée sous la forme d'une membrane selon l'une quelconque des revendications précédentes 1 à 37, la membrane possédant une épaisseur située entre 5 et 1 000 µm.
42. Procédé de production d'une membrane polymère selon la revendication 41, dans lequel
la quantité de monomère précipité dans la composition polymère siliconée est de 5
% en poids ou moins.
43. Procédé de production d'une membrane polymère selon l'une quelconque des revendications
41 et 42, dans lequel la membrane est une membrane pour la séparation des gaz ou des
liquides.
44. Procédé de production d'une membrane polymère selon l'une quelconque des revendications
41 et 42, dans lequel la membrane est une membrane de pile à combustible, ladite membrane
étant de préférence moins perméable aux gaz que la composition siliconée originale
d'au moins un facteur de 2, et moyennant quoi la conductivité pour les protons (H+)
est de préférence augmentée en comparaison avec la composition siliconée originale
par incorporation de monomères conducteurs de protons comme l'imidazole ou des dérivés
d'imidazole, la conductivité pour les protons (H+) étant de préférence accrue par
rapport à la composition siliconée originale d'un facteur d'au moins 10.
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